So what's up with this one? I've seen Joe Louis title defense claim to be represented 25-0 21 KO's and sometimes 26-0 22 KO's. It seems to me that Johnny Davis is a recent add to Louis record. having a 3-3 record, I can't imagine why he would be even considered as a title challanger.
Was Johnny Davis fight just a exhibition at one time and someone changed the status of that matchup?

All I see for an explaination is on Joe's boxrec record
"Heavyweight title at stake per New York State Athletic Commission ruling"

The story is that Louis came to town to box an exhibition, and the inexperienced clubfighter Johnny Davis was selected to be the other man in the ring. When giving his go-ahead for the bout, however, the chairman of the NYSAC unexpectedly announced that there were no such things as exhibitions and that the title was at stake whenever the champion faced a man under Queensberry rules.

Therefore, rather than take a chance of dropping a decision after four polite rounds of sparring, Louis strode out at the first bell and clobbered the poor guy in a matter of seconds.

So technically speaking it's a title defence - according to New York, anyway. But it's meaningless in terms of Louis' legacy.

The story is that Louis came to town to box an exhibition, and the inexperienced clubfighter Johnny Davis was selected to be the other man in the ring. When giving his go-ahead for the bout, however, the chairman of the NYSAC unexpectedly announced that there were no such things as exhibitions and that the title was at stake whenever the champion faced a man under Queensberry rules.

Therefore, rather than take a chance of dropping a decision after four polite rounds of sparring, Louis strode out at the first bell and clobbered the poor guy in a matter of seconds.

So technically speaking it's a title defence - according to New York, anyway. But it's meaningless in terms of Louis' legacy.